Sökning: "waveguides"

Visar resultat 1 - 5 av 136 avhandlingar innehållade ordet waveguides.

  1. 1. Schrödinger Operators in Waveguides

    Författare :Tomas Ekholm; Timo Weidl; Ari Laptev; Pavel Exner; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Schrödinger Operators; Hardy Inequalities; Mathematical physics; Matematisk fysik;

    Sammanfattning : In this thesis, which consists of four papers, we study the discrete spectrum of Schrödinger operators in waveguides. In these domains the quadratic form of the Dirichlet Laplacian operator does not satisfy any Hardy inequality. LÄS MER

  2. 2. Fluorinated polymer optical waveguides

    Författare :Claire Pitois; KTH; []
    Nyckelord :polymer; optical waveguide; telecommunications. Low-los passive wavguide; lithography; synthesis;

    Sammanfattning : .... LÄS MER

  3. 3. Miniaturized Hard Waveguides in Multifunction Array Antennas

    Författare :Malcolm Ng Mou Kehn; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interlaced arrays; Floquet theorem; reflector antennas; focal plane array; multifunction antennas; miniaturized waveguides; multilayer structures; spectral domain technique; periodic structures; aperture reuse; method of moments; soft and hard surfaces; array antennas;

    Sammanfattning : Recent advances in technologies of wireless communications systems have led to an increasing desire for several antennas performing diverse functions at different frequencies to be integrated into a common radiating aperture. This gives rise to the so-called multifunction antenna, which affords the saving of scarce premium real estate and can alleviate problems arising from excessive antenna protrusions in aspects such as aerodynamics, aesthetics, and stealth capability in military applications. LÄS MER

  4. 4. Ultralow-loss silicon nitride waveguides for nonlinear optics

    Författare :Zhichao Ye; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ultralow loss; Kerr nonlinear optics; parametric amplifier; DKS microcombs; integrated waveguides; silicon nitride;

    Sammanfattning : The field of nonlinear optics relies on the interaction between high-intensity optical waves and nonlinear media. An integrated waveguide with large refractive index contrast allows to highly confine optical waves in a sub-μm^2 area, thus enhancing the optical intensity. LÄS MER

  5. 5. Horizontal Slot Waveguides for Silicon Photonics Back-End Integration

    Författare :Maziar A. M. Naiini; Mikael Östling; Jörge Schulze; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silicon photonics; slot waveguides; grating couplers; CMOS tech- nology; high-k; ALD; germanium photodetectors; graphene photodetectors; pho- tonic integrated circuits;

    Sammanfattning : This thesis presents the development of integrated silicon photonic devices. These devices are compatible with the present and near future CMOS technology. High-khorizontal grating couplers and waveguides are proposed. LÄS MER